Scour characteristics downstream of grade-control structures

River restoration structure’s design features are some of the most important topics for hydraulic engineers. These low-environmental impact structures minimize the impact on natural contexts and at the same time, they do not require frequent anthropic intervention. Generally, these structures are used for river restoration and represent a dynamic system for both river grade-controlling and improving the aquatic habitat. The present paper aims to compare scour downstream of two different low-head rock made control structures; cross-vane and W-weir. The analysis involves the results of laboratory experiments conducted at the PITLAB hydraulic laboratory of University of Pisa and a detailed comparison of scour hole characteristics, highlighting similitudes and differences in the respective ranges of application. All tests are done in clear water conditions using uniform sand as channel bed material.